xref: /illumos-gate/usr/src/uts/common/io/idm/idm_conn_sm.c (revision b31b5de1357c915fe7dab4d9646d9d84f9fe69bc)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/cpuvar.h>
28 #include <sys/ddi.h>
29 #include <sys/sunddi.h>
30 #include <sys/modctl.h>
31 #include <sys/socket.h>
32 #include <sys/strsubr.h>
33 #include <sys/note.h>
34 #include <sys/sdt.h>
35 
36 #define	IDM_CONN_SM_STRINGS
37 #define	IDM_CN_NOTIFY_STRINGS
38 #include <sys/idm/idm.h>
39 
40 boolean_t	idm_sm_logging = B_FALSE;
41 
42 extern idm_global_t	idm; /* Global state */
43 
44 static void
45 idm_conn_event_handler(void *event_ctx_opaque);
46 
47 static void
48 idm_state_s1_free(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
49 
50 static void
51 idm_state_s2_xpt_wait(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
52 
53 static void
54 idm_state_s3_xpt_up(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
55 
56 static void
57 idm_state_s4_in_login(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
58 
59 static void
60 idm_state_s5_logged_in(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
61 
62 static void
63 idm_state_s6_in_logout(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
64 
65 static void
66 idm_logout_req_timeout(void *arg);
67 
68 static void
69 idm_state_s7_logout_req(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
70 
71 static void
72 idm_state_s8_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
73 
74 static void
75 idm_state_s9_init_error(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
76 
77 static void
78 idm_state_s9a_rejected(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
79 
80 static void
81 idm_state_s10_in_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
82 
83 static void
84 idm_state_s11_complete(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
85 
86 static void
87 idm_state_s12_enable_dm(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
88 
89 static void
90 idm_update_state(idm_conn_t *ic, idm_conn_state_t new_state,
91     idm_conn_event_ctx_t *event_ctx);
92 
93 static void
94 idm_conn_unref(void *ic_void);
95 
96 static void
97 idm_conn_reject_unref(void *ic_void);
98 
99 static idm_pdu_event_action_t
100 idm_conn_sm_validate_pdu(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx,
101     idm_pdu_t *pdu);
102 
103 static idm_status_t
104 idm_ffp_enable(idm_conn_t *ic);
105 
106 static void
107 idm_ffp_disable(idm_conn_t *ic, idm_ffp_disable_t disable_type);
108 
109 static void
110 idm_initial_login_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
111 
112 static void
113 idm_login_success_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx);
114 
115 idm_status_t
116 idm_conn_sm_init(idm_conn_t *ic)
117 {
118 	char taskq_name[32];
119 
120 	/*
121 	 * Caller should have assigned a unique connection ID.  Use this
122 	 * connection ID to create a unique connection name string
123 	 */
124 	ASSERT(ic->ic_internal_cid != 0);
125 	(void) snprintf(taskq_name, sizeof (taskq_name) - 1, "conn_sm%08x",
126 	    ic->ic_internal_cid);
127 
128 	ic->ic_state_taskq = taskq_create(taskq_name, 1, minclsyspri, 4, 16384,
129 	    TASKQ_PREPOPULATE);
130 	if (ic->ic_state_taskq == NULL) {
131 		return (IDM_STATUS_FAIL);
132 	}
133 
134 	idm_sm_audit_init(&ic->ic_state_audit);
135 	mutex_init(&ic->ic_state_mutex, NULL, MUTEX_DEFAULT, NULL);
136 	cv_init(&ic->ic_state_cv, NULL, CV_DEFAULT, NULL);
137 
138 	ic->ic_state = CS_S1_FREE;
139 	ic->ic_last_state = CS_S1_FREE;
140 
141 	return (IDM_STATUS_SUCCESS);
142 }
143 
144 void
145 idm_conn_sm_fini(idm_conn_t *ic)
146 {
147 
148 	/*
149 	 * The connection may only be partially created. If there
150 	 * is no taskq, then the connection SM was not initialized.
151 	 */
152 	if (ic->ic_state_taskq == NULL) {
153 		return;
154 	}
155 
156 	taskq_destroy(ic->ic_state_taskq);
157 
158 	cv_destroy(&ic->ic_state_cv);
159 	/*
160 	 * The thread that generated the event that got us here may still
161 	 * hold the ic_state_mutex. Once it is released we can safely
162 	 * destroy it since there is no way to locate the object now.
163 	 */
164 	mutex_enter(&ic->ic_state_mutex);
165 	mutex_destroy(&ic->ic_state_mutex);
166 }
167 
168 void
169 idm_conn_event(idm_conn_t *ic, idm_conn_event_t event, uintptr_t event_info)
170 {
171 	mutex_enter(&ic->ic_state_mutex);
172 	idm_conn_event_locked(ic, event, event_info, CT_NONE);
173 	mutex_exit(&ic->ic_state_mutex);
174 }
175 
176 
177 idm_status_t
178 idm_conn_reinstate_event(idm_conn_t *old_ic, idm_conn_t *new_ic)
179 {
180 	int result;
181 
182 	mutex_enter(&old_ic->ic_state_mutex);
183 	if (((old_ic->ic_conn_type == CONN_TYPE_INI) &&
184 	    (old_ic->ic_state != CS_S8_CLEANUP)) ||
185 	    ((old_ic->ic_conn_type == CONN_TYPE_TGT) &&
186 	    (old_ic->ic_state < CS_S5_LOGGED_IN))) {
187 		result = IDM_STATUS_FAIL;
188 	} else {
189 		result = IDM_STATUS_SUCCESS;
190 		new_ic->ic_reinstate_conn = old_ic;
191 		idm_conn_event_locked(new_ic->ic_reinstate_conn,
192 		    CE_CONN_REINSTATE, (uintptr_t)new_ic, CT_NONE);
193 	}
194 	mutex_exit(&old_ic->ic_state_mutex);
195 
196 	return (result);
197 }
198 
199 void
200 idm_conn_tx_pdu_event(idm_conn_t *ic, idm_conn_event_t event,
201     uintptr_t event_info)
202 {
203 	ASSERT(mutex_owned(&ic->ic_state_mutex));
204 	ic->ic_pdu_events++;
205 	idm_conn_event_locked(ic, event, event_info, CT_TX_PDU);
206 }
207 
208 void
209 idm_conn_rx_pdu_event(idm_conn_t *ic, idm_conn_event_t event,
210     uintptr_t event_info)
211 {
212 	ASSERT(mutex_owned(&ic->ic_state_mutex));
213 	ic->ic_pdu_events++;
214 	idm_conn_event_locked(ic, event, event_info, CT_RX_PDU);
215 }
216 
217 void
218 idm_conn_event_locked(idm_conn_t *ic, idm_conn_event_t event,
219     uintptr_t event_info, idm_pdu_event_type_t pdu_event_type)
220 {
221 	idm_conn_event_ctx_t	*event_ctx;
222 
223 	idm_sm_audit_event(&ic->ic_state_audit, SAS_IDM_CONN,
224 	    (int)ic->ic_state, (int)event, event_info);
225 
226 	/*
227 	 * It's very difficult to prevent a few straggling events
228 	 * at the end.  For example idm_sorx_thread will generate
229 	 * a CE_TRANSPORT_FAIL event when it exits.  Rather than
230 	 * push complicated restrictions all over the code to
231 	 * prevent this we will simply drop the events (and in
232 	 * the case of PDU events release them appropriately)
233 	 * since they are irrelevant once we are in a terminal state.
234 	 * Of course those threads need to have appropriate holds on
235 	 * the connection otherwise it might disappear.
236 	 */
237 	if ((ic->ic_state == CS_S9_INIT_ERROR) ||
238 	    (ic->ic_state == CS_S9A_REJECTED) ||
239 	    (ic->ic_state == CS_S11_COMPLETE)) {
240 		if ((pdu_event_type == CT_TX_PDU) ||
241 		    (pdu_event_type == CT_RX_PDU)) {
242 			ic->ic_pdu_events--;
243 			idm_pdu_complete((idm_pdu_t *)event_info,
244 			    IDM_STATUS_SUCCESS);
245 		}
246 		IDM_SM_LOG(CE_NOTE, "*** Dropping event %s (%d) because of"
247 		    "state %s (%d)",
248 		    idm_ce_name[event], event,
249 		    idm_cs_name[ic->ic_state], ic->ic_state);
250 		return;
251 	}
252 
253 	/*
254 	 * Normal event handling
255 	 */
256 	idm_conn_hold(ic);
257 
258 	event_ctx = kmem_zalloc(sizeof (*event_ctx), KM_SLEEP);
259 	event_ctx->iec_ic = ic;
260 	event_ctx->iec_event = event;
261 	event_ctx->iec_info = event_info;
262 	event_ctx->iec_pdu_event_type = pdu_event_type;
263 
264 	(void) taskq_dispatch(ic->ic_state_taskq, &idm_conn_event_handler,
265 	    event_ctx, TQ_SLEEP);
266 }
267 
268 static void
269 idm_conn_event_handler(void *event_ctx_opaque)
270 {
271 	idm_conn_event_ctx_t *event_ctx = event_ctx_opaque;
272 	idm_conn_t *ic = event_ctx->iec_ic;
273 	idm_pdu_t *pdu = (idm_pdu_t *)event_ctx->iec_info;
274 	idm_pdu_event_action_t action;
275 
276 	IDM_SM_LOG(CE_NOTE, "idm_conn_event_handler: conn %p event %s(%d)",
277 	    (void *)ic, idm_ce_name[event_ctx->iec_event],
278 	    event_ctx->iec_event);
279 	DTRACE_PROBE2(conn__event,
280 	    idm_conn_t *, ic, idm_conn_event_ctx_t *, event_ctx);
281 
282 	/*
283 	 * Validate event
284 	 */
285 	ASSERT(event_ctx->iec_event != CE_UNDEFINED);
286 	ASSERT3U(event_ctx->iec_event, <, CE_MAX_EVENT);
287 
288 	/*
289 	 * Validate current state
290 	 */
291 	ASSERT(ic->ic_state != CS_S0_UNDEFINED);
292 	ASSERT3U(ic->ic_state, <, CS_MAX_STATE);
293 
294 	/*
295 	 * Validate PDU-related events against the current state.  If a PDU
296 	 * is not allowed in the current state we change the event to a
297 	 * protocol error.  This simplifies the state-specific event handlers.
298 	 * For example the CS_S2_XPT_WAIT state only needs to handle the
299 	 * CE_TX_PROTOCOL_ERROR and CE_RX_PROTOCOL_ERROR events since
300 	 * no PDU's can be transmitted or received in that state.
301 	 */
302 	event_ctx->iec_pdu_forwarded = B_FALSE;
303 	if (event_ctx->iec_pdu_event_type != CT_NONE) {
304 		ASSERT(pdu != NULL);
305 		action = idm_conn_sm_validate_pdu(ic, event_ctx, pdu);
306 
307 		switch (action) {
308 		case CA_TX_PROTOCOL_ERROR:
309 			/*
310 			 * Change event and forward the PDU
311 			 */
312 			event_ctx->iec_event = CE_TX_PROTOCOL_ERROR;
313 			break;
314 		case CA_RX_PROTOCOL_ERROR:
315 			/*
316 			 * Change event and forward the PDU.
317 			 */
318 			event_ctx->iec_event = CE_RX_PROTOCOL_ERROR;
319 			break;
320 		case CA_FORWARD:
321 			/*
322 			 * Let the state-specific event handlers take
323 			 * care of it.
324 			 */
325 			break;
326 		case CA_DROP:
327 			/*
328 			 * It never even happened
329 			 */
330 			IDM_SM_LOG(CE_NOTE, "*** drop PDU %p", (void *) pdu);
331 			idm_pdu_complete(pdu, IDM_STATUS_FAIL);
332 			break;
333 		default:
334 			ASSERT(0);
335 			break;
336 		}
337 	}
338 
339 	switch (ic->ic_state) {
340 	case CS_S1_FREE:
341 		idm_state_s1_free(ic, event_ctx);
342 		break;
343 	case CS_S2_XPT_WAIT:
344 		idm_state_s2_xpt_wait(ic, event_ctx);
345 		break;
346 	case CS_S3_XPT_UP:
347 		idm_state_s3_xpt_up(ic, event_ctx);
348 		break;
349 	case CS_S4_IN_LOGIN:
350 		idm_state_s4_in_login(ic, event_ctx);
351 		break;
352 	case CS_S5_LOGGED_IN:
353 		idm_state_s5_logged_in(ic, event_ctx);
354 		break;
355 	case CS_S6_IN_LOGOUT:
356 		idm_state_s6_in_logout(ic, event_ctx);
357 		break;
358 	case CS_S7_LOGOUT_REQ:
359 		idm_state_s7_logout_req(ic, event_ctx);
360 		break;
361 	case CS_S8_CLEANUP:
362 		idm_state_s8_cleanup(ic, event_ctx);
363 		break;
364 	case CS_S9A_REJECTED:
365 		idm_state_s9a_rejected(ic, event_ctx);
366 		break;
367 	case CS_S9_INIT_ERROR:
368 		idm_state_s9_init_error(ic, event_ctx);
369 		break;
370 	case CS_S10_IN_CLEANUP:
371 		idm_state_s10_in_cleanup(ic, event_ctx);
372 		break;
373 	case CS_S11_COMPLETE:
374 		idm_state_s11_complete(ic, event_ctx);
375 		break;
376 	case CS_S12_ENABLE_DM:
377 		idm_state_s12_enable_dm(ic, event_ctx);
378 		break;
379 	default:
380 		ASSERT(0);
381 		break;
382 	}
383 
384 	/*
385 	 * Now that we've updated the state machine, if this was
386 	 * a PDU-related event take the appropriate action on the PDU
387 	 * (transmit it, forward it to the clients RX callback, drop
388 	 * it, etc).
389 	 */
390 	if (event_ctx->iec_pdu_event_type != CT_NONE) {
391 		switch (action) {
392 		case CA_TX_PROTOCOL_ERROR:
393 			idm_pdu_tx_protocol_error(ic, pdu);
394 			break;
395 		case CA_RX_PROTOCOL_ERROR:
396 			idm_pdu_rx_protocol_error(ic, pdu);
397 			break;
398 		case CA_FORWARD:
399 			if (!event_ctx->iec_pdu_forwarded) {
400 				if (event_ctx->iec_pdu_event_type ==
401 				    CT_RX_PDU) {
402 					idm_pdu_rx_forward(ic, pdu);
403 				} else {
404 					idm_pdu_tx_forward(ic, pdu);
405 				}
406 			}
407 			break;
408 		default:
409 			ASSERT(0);
410 			break;
411 		}
412 	}
413 
414 	/*
415 	 * Update outstanding PDU event count (see idm_pdu_tx for
416 	 * how this is used)
417 	 */
418 	if ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ||
419 	    (event_ctx->iec_pdu_event_type == CT_RX_PDU)) {
420 		mutex_enter(&ic->ic_state_mutex);
421 		ic->ic_pdu_events--;
422 		mutex_exit(&ic->ic_state_mutex);
423 	}
424 
425 	idm_conn_rele(ic);
426 	kmem_free(event_ctx, sizeof (*event_ctx));
427 }
428 
429 static void
430 idm_state_s1_free(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
431 {
432 	switch (event_ctx->iec_event) {
433 	case CE_CONNECT_REQ:
434 		/* T1 */
435 		idm_update_state(ic, CS_S2_XPT_WAIT, event_ctx);
436 		break;
437 	case CE_CONNECT_ACCEPT:
438 		/* T3 */
439 		idm_update_state(ic, CS_S3_XPT_UP, event_ctx);
440 		break;
441 	case CE_TX_PROTOCOL_ERROR:
442 	case CE_RX_PROTOCOL_ERROR:
443 		/* This should never happen */
444 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
445 		break;
446 	default:
447 		ASSERT(0);
448 		/*NOTREACHED*/
449 	}
450 }
451 
452 
453 static void
454 idm_state_s2_xpt_wait(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
455 {
456 	switch (event_ctx->iec_event) {
457 	case CE_CONNECT_SUCCESS:
458 		/* T4 */
459 		idm_update_state(ic, CS_S4_IN_LOGIN, event_ctx);
460 		break;
461 	case CE_CONNECT_FAIL:
462 	case CE_LOGOUT_OTHER_CONN_RCV:
463 	case CE_TX_PROTOCOL_ERROR:
464 	case CE_RX_PROTOCOL_ERROR:
465 		/* T2 */
466 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
467 		break;
468 	default:
469 		ASSERT(0);
470 		/*NOTREACHED*/
471 	}
472 }
473 
474 
475 static void
476 idm_login_timeout(void *arg)
477 {
478 	idm_conn_t *ic = arg;
479 
480 	idm_conn_event(ic, CE_LOGIN_TIMEOUT, NULL);
481 }
482 
483 static void
484 idm_state_s3_xpt_up(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
485 {
486 	switch (event_ctx->iec_event) {
487 	case CE_LOGIN_RCV:
488 		/* T4 */
489 		idm_initial_login_actions(ic, event_ctx);
490 		idm_update_state(ic, CS_S4_IN_LOGIN, event_ctx);
491 		break;
492 	case CE_LOGIN_TIMEOUT:
493 		/*
494 		 * Don't need to cancel login timer since the timer is
495 		 * presumed to be the source of this event.
496 		 */
497 		(void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
498 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
499 		break;
500 	case CE_CONNECT_REJECT:
501 		/*
502 		 * Iscsit doesn't want to hear from us again in this case.
503 		 * Since it rejected the connection it doesn't have a
504 		 * connection context to handle additional notifications.
505 		 * IDM needs to just clean things up on its own.
506 		 */
507 		(void) untimeout(ic->ic_state_timeout);
508 		idm_update_state(ic, CS_S9A_REJECTED, event_ctx);
509 		break;
510 	case CE_CONNECT_FAIL:
511 	case CE_TRANSPORT_FAIL:
512 	case CE_LOGOUT_OTHER_CONN_SND:
513 		/* T6 */
514 		(void) untimeout(ic->ic_state_timeout);
515 		(void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
516 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
517 		break;
518 	case CE_TX_PROTOCOL_ERROR:
519 	case CE_RX_PROTOCOL_ERROR:
520 		/* Don't care */
521 		break;
522 	default:
523 		ASSERT(0);
524 		/*NOTREACHED*/
525 	}
526 }
527 
528 static void
529 idm_state_s4_in_login_fail_snd_done(idm_pdu_t *pdu, idm_status_t status)
530 {
531 	idm_conn_t		*ic = pdu->isp_ic;
532 
533 	/*
534 	 * This pdu callback can be invoked by the tx thread,
535 	 * so run the disconnect code from another thread.
536 	 */
537 	pdu->isp_status = status;
538 	idm_conn_event(ic, CE_LOGIN_FAIL_SND_DONE, (uintptr_t)pdu);
539 }
540 
541 static void
542 idm_state_s4_in_login(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
543 {
544 	idm_pdu_t *pdu;
545 
546 	/*
547 	 * Login timer should no longer be active after leaving this
548 	 * state.
549 	 */
550 	switch (event_ctx->iec_event) {
551 	case CE_LOGIN_SUCCESS_RCV:
552 	case CE_LOGIN_SUCCESS_SND:
553 		(void) untimeout(ic->ic_state_timeout);
554 		idm_login_success_actions(ic, event_ctx);
555 		if (ic->ic_rdma_extensions) {
556 			/* T19 */
557 			idm_update_state(ic, CS_S12_ENABLE_DM, event_ctx);
558 		} else {
559 			/* T5 */
560 			idm_update_state(ic, CS_S5_LOGGED_IN, event_ctx);
561 		}
562 		break;
563 	case CE_LOGIN_TIMEOUT:
564 		/* T7 */
565 		(void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
566 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
567 		break;
568 	case CE_LOGIN_FAIL_SND_DONE:
569 		(void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
570 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
571 		break;
572 	case CE_LOGIN_FAIL_SND:
573 		/*
574 		 * Allow the logout response pdu to be sent and defer
575 		 * the state machine update until the completion callback.
576 		 * Only 1 level or callback interposition is allowed.
577 		 */
578 		(void) untimeout(ic->ic_state_timeout);
579 		pdu = (idm_pdu_t *)event_ctx->iec_info;
580 		ASSERT(ic->ic_client_callback == NULL);
581 		ic->ic_client_callback = pdu->isp_callback;
582 		pdu->isp_callback =
583 		    idm_state_s4_in_login_fail_snd_done;
584 		break;
585 	case CE_LOGIN_FAIL_RCV:
586 		/*
587 		 * Need to deliver this PDU to the initiator now because after
588 		 * we update the state to CS_S9_INIT_ERROR the initiator will
589 		 * no longer be in an appropriate state.
590 		 */
591 		event_ctx->iec_pdu_forwarded = B_TRUE;
592 		pdu = (idm_pdu_t *)event_ctx->iec_info;
593 		idm_pdu_rx_forward(ic, pdu);
594 		/* FALLTHROUGH */
595 	case CE_TRANSPORT_FAIL:
596 	case CE_LOGOUT_OTHER_CONN_SND:
597 	case CE_LOGOUT_OTHER_CONN_RCV:
598 		/* T7 */
599 		(void) untimeout(ic->ic_state_timeout);
600 		(void) idm_notify_client(ic, CN_LOGIN_FAIL, NULL);
601 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
602 		break;
603 	case CE_LOGIN_SND:
604 		/*
605 		 * Initiator connections will see initial login PDU
606 		 * in this state.  Target connections see initial
607 		 * login PDU in "xpt up" state.
608 		 */
609 		mutex_enter(&ic->ic_state_mutex);
610 		if (!(ic->ic_state_flags & CF_INITIAL_LOGIN)) {
611 			idm_initial_login_actions(ic, event_ctx);
612 		}
613 		mutex_exit(&ic->ic_state_mutex);
614 		break;
615 	case CE_MISC_TX:
616 	case CE_MISC_RX:
617 	case CE_LOGIN_RCV:
618 	case CE_TX_PROTOCOL_ERROR:
619 	case CE_RX_PROTOCOL_ERROR:
620 		/* Don't care */
621 		break;
622 	default:
623 		ASSERT(0);
624 		/*NOTREACHED*/
625 	}
626 }
627 
628 
629 static void
630 idm_state_s5_logged_in(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
631 {
632 	switch (event_ctx->iec_event) {
633 	case CE_LOGOUT_THIS_CONN_RCV:
634 	case CE_LOGOUT_THIS_CONN_SND:
635 	case CE_LOGOUT_OTHER_CONN_RCV:
636 	case CE_LOGOUT_OTHER_CONN_SND:
637 		/* T9 */
638 		idm_ffp_disable(ic, FD_CONN_LOGOUT); /* Explicit logout */
639 		idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
640 		break;
641 	case CE_LOGOUT_SESSION_RCV:
642 	case CE_LOGOUT_SESSION_SND:
643 		/* T9 */
644 		idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */
645 		idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
646 		break;
647 	case CE_LOGOUT_SESSION_SUCCESS:
648 		/* T8 */
649 		idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */
650 
651 		/* Close connection */
652 		if (IDM_CONN_ISTGT(ic)) {
653 			ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
654 		} else {
655 			ic->ic_transport_ops->it_ini_conn_disconnect(ic);
656 		}
657 
658 		idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
659 		break;
660 	case CE_ASYNC_LOGOUT_RCV:
661 	case CE_ASYNC_LOGOUT_SND:
662 		/* T11 */
663 		idm_update_state(ic, CS_S7_LOGOUT_REQ, event_ctx);
664 		break;
665 	case CE_TRANSPORT_FAIL:
666 	case CE_ASYNC_DROP_CONN_RCV:
667 	case CE_ASYNC_DROP_CONN_SND:
668 	case CE_ASYNC_DROP_ALL_CONN_RCV:
669 	case CE_ASYNC_DROP_ALL_CONN_SND:
670 		/* T15 */
671 		idm_ffp_disable(ic, FD_CONN_FAIL); /* Implicit logout */
672 		idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
673 		break;
674 	case CE_MISC_TX:
675 	case CE_MISC_RX:
676 	case CE_TX_PROTOCOL_ERROR:
677 	case CE_RX_PROTOCOL_ERROR:
678 		/* Don't care */
679 		break;
680 	default:
681 		ASSERT(0);
682 	}
683 }
684 
685 static void
686 idm_state_s6_in_logout_success_snd_done(idm_pdu_t *pdu, idm_status_t status)
687 {
688 	idm_conn_t		*ic = pdu->isp_ic;
689 
690 	/*
691 	 * This pdu callback can be invoked by the tx thread,
692 	 * so run the disconnect code from another thread.
693 	 */
694 	pdu->isp_status = status;
695 	idm_conn_event(ic, CE_LOGOUT_SUCCESS_SND_DONE, (uintptr_t)pdu);
696 }
697 
698 static void
699 idm_state_s6_in_logout_fail_snd_done(idm_pdu_t *pdu, idm_status_t status)
700 {
701 	idm_conn_t		*ic = pdu->isp_ic;
702 
703 	/*
704 	 * This pdu callback can be invoked by the tx thread,
705 	 * so run the disconnect code from another thread.
706 	 */
707 	pdu->isp_status = status;
708 	idm_conn_event(ic, CE_LOGOUT_FAIL_SND_DONE, (uintptr_t)pdu);
709 }
710 
711 static void
712 idm_state_s6_in_logout(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
713 {
714 	idm_pdu_t *pdu;
715 
716 	switch (event_ctx->iec_event) {
717 	case CE_LOGOUT_SUCCESS_SND_DONE:
718 		pdu = (idm_pdu_t *)event_ctx->iec_info;
719 
720 		/* Close connection (if it's not already closed) */
721 		ASSERT(IDM_CONN_ISTGT(ic));
722 		ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
723 
724 		/* restore client callback */
725 		pdu->isp_callback =  ic->ic_client_callback;
726 		ic->ic_client_callback = NULL;
727 		idm_pdu_complete(pdu, pdu->isp_status);
728 		idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
729 		break;
730 	case CE_LOGOUT_FAIL_SND_DONE:
731 		pdu = (idm_pdu_t *)event_ctx->iec_info;
732 		/* restore client callback */
733 		pdu->isp_callback =  ic->ic_client_callback;
734 		ic->ic_client_callback = NULL;
735 		idm_pdu_complete(pdu, pdu->isp_status);
736 		idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
737 		break;
738 	case CE_LOGOUT_SUCCESS_SND:
739 	case CE_LOGOUT_FAIL_SND:
740 		/*
741 		 * Allow the logout response pdu to be sent and defer
742 		 * the state machine update until the completion callback.
743 		 * Only 1 level or callback interposition is allowed.
744 		 */
745 		pdu = (idm_pdu_t *)event_ctx->iec_info;
746 		ASSERT(ic->ic_client_callback == NULL);
747 		ic->ic_client_callback = pdu->isp_callback;
748 		if (event_ctx->iec_event == CE_LOGOUT_SUCCESS_SND) {
749 			pdu->isp_callback =
750 			    idm_state_s6_in_logout_success_snd_done;
751 		} else {
752 			pdu->isp_callback =
753 			    idm_state_s6_in_logout_fail_snd_done;
754 		}
755 		break;
756 	case CE_LOGOUT_SUCCESS_RCV:
757 		/*
758 		 * Need to deliver this PDU to the initiator now because after
759 		 * we update the state to CS_S11_COMPLETE the initiator will
760 		 * no longer be in an appropriate state.
761 		 */
762 		event_ctx->iec_pdu_forwarded = B_TRUE;
763 		pdu = (idm_pdu_t *)event_ctx->iec_info;
764 		idm_pdu_rx_forward(ic, pdu);
765 		/* FALLTHROUGH */
766 	case CE_LOGOUT_SESSION_SUCCESS:
767 		/* T13 */
768 
769 		/* Close connection (if it's not already closed) */
770 		if (IDM_CONN_ISTGT(ic)) {
771 			ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
772 		} else {
773 			ic->ic_transport_ops->it_ini_conn_disconnect(ic);
774 		}
775 
776 		idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
777 		break;
778 	case CE_ASYNC_LOGOUT_RCV:
779 		/* T14 Do nothing */
780 		break;
781 	case CE_TRANSPORT_FAIL:
782 	case CE_ASYNC_DROP_CONN_RCV:
783 	case CE_ASYNC_DROP_CONN_SND:
784 	case CE_ASYNC_DROP_ALL_CONN_RCV:
785 	case CE_ASYNC_DROP_ALL_CONN_SND:
786 	case CE_LOGOUT_FAIL_RCV:
787 		idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
788 		break;
789 	case CE_TX_PROTOCOL_ERROR:
790 	case CE_RX_PROTOCOL_ERROR:
791 	case CE_MISC_TX:
792 	case CE_MISC_RX:
793 		/* Don't care */
794 		break;
795 	default:
796 		ASSERT(0);
797 	}
798 }
799 
800 
801 static void
802 idm_logout_req_timeout(void *arg)
803 {
804 	idm_conn_t *ic = arg;
805 
806 	idm_conn_event(ic, CE_LOGOUT_TIMEOUT, NULL);
807 }
808 
809 static void
810 idm_state_s7_logout_req(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
811 {
812 	/* Must cancel logout timer before leaving this state */
813 	switch (event_ctx->iec_event) {
814 	case CE_LOGOUT_THIS_CONN_RCV:
815 	case CE_LOGOUT_THIS_CONN_SND:
816 	case CE_LOGOUT_OTHER_CONN_RCV:
817 	case CE_LOGOUT_OTHER_CONN_SND:
818 		/* T10 */
819 		if (IDM_CONN_ISTGT(ic)) {
820 			(void) untimeout(ic->ic_state_timeout);
821 		}
822 		idm_ffp_disable(ic, FD_CONN_LOGOUT); /* Explicit logout */
823 		idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
824 		break;
825 	case CE_LOGOUT_SESSION_RCV:
826 	case CE_LOGOUT_SESSION_SND:
827 		/* T10 */
828 		if (IDM_CONN_ISTGT(ic)) {
829 			(void) untimeout(ic->ic_state_timeout);
830 		}
831 		idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */
832 		idm_update_state(ic, CS_S6_IN_LOGOUT, event_ctx);
833 		break;
834 	case CE_ASYNC_LOGOUT_RCV:
835 	case CE_ASYNC_LOGOUT_SND:
836 		/* T12 Do nothing */
837 		break;
838 	case CE_TRANSPORT_FAIL:
839 	case CE_ASYNC_DROP_CONN_RCV:
840 	case CE_ASYNC_DROP_CONN_SND:
841 	case CE_ASYNC_DROP_ALL_CONN_RCV:
842 	case CE_ASYNC_DROP_ALL_CONN_SND:
843 		/* T16 */
844 		if (IDM_CONN_ISTGT(ic)) {
845 			(void) untimeout(ic->ic_state_timeout);
846 		}
847 		/* FALLTHROUGH */
848 	case CE_LOGOUT_TIMEOUT:
849 		idm_ffp_disable(ic, FD_CONN_FAIL); /* Implicit logout */
850 		idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
851 		break;
852 	case CE_LOGOUT_SESSION_SUCCESS:
853 		/* T18 */
854 		if (IDM_CONN_ISTGT(ic)) {
855 			(void) untimeout(ic->ic_state_timeout);
856 		}
857 		idm_ffp_disable(ic, FD_SESS_LOGOUT); /* Explicit logout */
858 
859 		/* Close connection (if it's not already closed) */
860 		if (IDM_CONN_ISTGT(ic)) {
861 			ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
862 		} else {
863 			ic->ic_transport_ops->it_ini_conn_disconnect(ic);
864 		}
865 
866 		idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
867 		break;
868 	case CE_TX_PROTOCOL_ERROR:
869 	case CE_RX_PROTOCOL_ERROR:
870 	case CE_MISC_TX:
871 	case CE_MISC_RX:
872 		/* Don't care */
873 		break;
874 	default:
875 		ASSERT(0);
876 	}
877 }
878 
879 
880 static void
881 idm_cleanup_timeout(void *arg)
882 {
883 	idm_conn_t *ic = arg;
884 
885 	idm_conn_event(ic, CE_CLEANUP_TIMEOUT, NULL);
886 }
887 
888 static void
889 idm_state_s8_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
890 {
891 	idm_pdu_t *pdu;
892 
893 	/*
894 	 * Need to cancel the cleanup timeout before leaving this state
895 	 * if it hasn't already fired.
896 	 */
897 	switch (event_ctx->iec_event) {
898 	case CE_LOGOUT_SUCCESS_RCV:
899 	case CE_LOGOUT_SUCCESS_SND:
900 	case CE_LOGOUT_SESSION_SUCCESS:
901 		(void) untimeout(ic->ic_state_timeout);
902 		/*FALLTHROUGH*/
903 	case CE_CLEANUP_TIMEOUT:
904 		/* M1 */
905 		idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
906 		break;
907 	case CE_LOGOUT_OTHER_CONN_RCV:
908 	case CE_LOGOUT_OTHER_CONN_SND:
909 		/* M2 */
910 		idm_update_state(ic, CS_S10_IN_CLEANUP, event_ctx);
911 		break;
912 	case CE_LOGOUT_SUCCESS_SND_DONE:
913 	case CE_LOGOUT_FAIL_SND_DONE:
914 		pdu = (idm_pdu_t *)event_ctx->iec_info;
915 		/* restore client callback */
916 		pdu->isp_callback =  ic->ic_client_callback;
917 		ic->ic_client_callback = NULL;
918 		idm_pdu_complete(pdu, pdu->isp_status);
919 		break;
920 	case CE_LOGOUT_SESSION_RCV:
921 	case CE_LOGOUT_SESSION_SND:
922 	case CE_TX_PROTOCOL_ERROR:
923 	case CE_RX_PROTOCOL_ERROR:
924 	case CE_MISC_TX:
925 	case CE_MISC_RX:
926 	case CE_TRANSPORT_FAIL:
927 	case CE_LOGOUT_TIMEOUT:
928 		/* Don't care */
929 		break;
930 	default:
931 		ASSERT(0);
932 	}
933 }
934 
935 /* ARGSUSED */
936 static void
937 idm_state_s9_init_error(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
938 {
939 	if (ic->ic_conn_type == CONN_TYPE_INI) {
940 		mutex_enter(&ic->ic_state_mutex);
941 		ic->ic_state_flags |= CF_ERROR;
942 		ic->ic_conn_sm_status = IDM_STATUS_FAIL;
943 		cv_signal(&ic->ic_state_cv);
944 		mutex_exit(&ic->ic_state_mutex);
945 	}
946 }
947 
948 /* ARGSUSED */
949 static void
950 idm_state_s9a_rejected(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
951 {
952 	/* Ignore events */
953 }
954 
955 static void
956 idm_state_s10_in_cleanup(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
957 {
958 	idm_pdu_t *pdu;
959 
960 	/*
961 	 * Need to cancel the cleanup timeout before leaving this state
962 	 * if it hasn't already fired.
963 	 */
964 	switch (event_ctx->iec_event) {
965 	case CE_LOGOUT_FAIL_RCV:
966 	case CE_LOGOUT_FAIL_SND:
967 		idm_update_state(ic, CS_S8_CLEANUP, event_ctx);
968 		break;
969 	case CE_LOGOUT_SUCCESS_SND:
970 	case CE_LOGOUT_SUCCESS_RCV:
971 	case CE_LOGOUT_SESSION_SUCCESS:
972 		(void) untimeout(ic->ic_state_timeout);
973 		/*FALLTHROUGH*/
974 	case CE_CLEANUP_TIMEOUT:
975 		idm_update_state(ic, CS_S11_COMPLETE, event_ctx);
976 		break;
977 	case CE_LOGOUT_SUCCESS_SND_DONE:
978 	case CE_LOGOUT_FAIL_SND_DONE:
979 		pdu = (idm_pdu_t *)event_ctx->iec_info;
980 		/* restore client callback */
981 		pdu->isp_callback =  ic->ic_client_callback;
982 		ic->ic_client_callback = NULL;
983 		idm_pdu_complete(pdu, pdu->isp_status);
984 		break;
985 	case CE_TX_PROTOCOL_ERROR:
986 	case CE_RX_PROTOCOL_ERROR:
987 	case CE_MISC_TX:
988 	case CE_MISC_RX:
989 	case CE_LOGOUT_TIMEOUT:
990 		/* Don't care */
991 		break;
992 	default:
993 		ASSERT(0);
994 	}
995 }
996 
997 /* ARGSUSED */
998 static void
999 idm_state_s11_complete(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
1000 {
1001 	idm_pdu_t *pdu;
1002 
1003 	/*
1004 	 * Cleanup logout success/fail completion if it's been delayed
1005 	 * until now.
1006 	 */
1007 	switch (event_ctx->iec_event) {
1008 	case CE_LOGOUT_SUCCESS_SND_DONE:
1009 	case CE_LOGOUT_FAIL_SND_DONE:
1010 		pdu = (idm_pdu_t *)event_ctx->iec_info;
1011 		/* restore client callback */
1012 		pdu->isp_callback =  ic->ic_client_callback;
1013 		ic->ic_client_callback = NULL;
1014 		idm_pdu_complete(pdu, pdu->isp_status);
1015 		break;
1016 	}
1017 }
1018 
1019 static void
1020 idm_state_s12_enable_dm(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
1021 {
1022 	switch (event_ctx->iec_event) {
1023 	case CE_ENABLE_DM_SUCCESS:
1024 		/* T20 */
1025 		idm_update_state(ic, CS_S5_LOGGED_IN, event_ctx);
1026 		break;
1027 	case CE_ENABLE_DM_FAIL:
1028 		/* T21 */
1029 		idm_update_state(ic, CS_S9_INIT_ERROR, event_ctx);
1030 		break;
1031 	case CE_TRANSPORT_FAIL:
1032 		/*
1033 		 * We expect to always hear back from the transport layer
1034 		 * once we have an "enable data-mover" request outstanding.
1035 		 * Therefore we'll ignore other events that may occur even
1036 		 * when they clearly indicate a problem and wait for
1037 		 * CE_ENABLE_DM_FAIL.  On a related note this means the
1038 		 * transport must ensure that it eventually completes the
1039 		 * "enable data-mover" operation with either success or
1040 		 * failure -- otherwise we'll be stuck here.
1041 		 */
1042 		break;
1043 	default:
1044 		ASSERT(0);
1045 		break;
1046 	}
1047 }
1048 
1049 static void
1050 idm_update_state(idm_conn_t *ic, idm_conn_state_t new_state,
1051     idm_conn_event_ctx_t *event_ctx)
1052 {
1053 	int rc;
1054 	idm_status_t idm_status;
1055 
1056 	/*
1057 	 * Validate new state
1058 	 */
1059 	ASSERT(new_state != CS_S0_UNDEFINED);
1060 	ASSERT3U(new_state, <, CS_MAX_STATE);
1061 
1062 	/*
1063 	 * Update state in context.  We protect this with a mutex
1064 	 * even though the state machine code is single threaded so that
1065 	 * other threads can check the state value atomically.
1066 	 */
1067 	new_state = (new_state < CS_MAX_STATE) ?
1068 	    new_state : CS_S0_UNDEFINED;
1069 
1070 	IDM_SM_LOG(CE_NOTE, "idm_update_state: conn %p, evt %s(%d), "
1071 	    "%s(%d) --> %s(%d)", (void *)ic,
1072 	    idm_ce_name[event_ctx->iec_event], event_ctx->iec_event,
1073 	    idm_cs_name[ic->ic_state], ic->ic_state,
1074 	    idm_cs_name[new_state], new_state);
1075 
1076 	DTRACE_PROBE2(conn__state__change,
1077 	    idm_conn_t *, ic, idm_conn_state_t, new_state);
1078 
1079 	mutex_enter(&ic->ic_state_mutex);
1080 	idm_sm_audit_state_change(&ic->ic_state_audit, SAS_IDM_CONN,
1081 	    (int)ic->ic_state, (int)new_state);
1082 	ic->ic_last_state = ic->ic_state;
1083 	ic->ic_state = new_state;
1084 	cv_signal(&ic->ic_state_cv);
1085 	mutex_exit(&ic->ic_state_mutex);
1086 
1087 	switch (ic->ic_state) {
1088 	case CS_S1_FREE:
1089 		ASSERT(0); /* Initial state, can't return */
1090 		break;
1091 	case CS_S2_XPT_WAIT:
1092 		if ((rc = idm_ini_conn_finish(ic)) != 0) {
1093 			idm_conn_event(ic, CE_CONNECT_FAIL, NULL);
1094 		} else {
1095 			idm_conn_event(ic, CE_CONNECT_SUCCESS, NULL);
1096 		}
1097 		break;
1098 	case CS_S3_XPT_UP:
1099 		/*
1100 		 * Finish any connection related setup including
1101 		 * waking up the idm_tgt_conn_accept thread.
1102 		 * and starting the login timer.  If the function
1103 		 * fails then we return to "free" state.
1104 		 */
1105 		if ((rc = idm_tgt_conn_finish(ic)) != IDM_STATUS_SUCCESS) {
1106 			switch (rc) {
1107 			case IDM_STATUS_REJECT:
1108 				idm_conn_event(ic, CE_CONNECT_REJECT, NULL);
1109 				break;
1110 			default:
1111 				idm_conn_event(ic, CE_CONNECT_FAIL, NULL);
1112 				break;
1113 			}
1114 		}
1115 
1116 		/*
1117 		 * First login received will cause a transition to
1118 		 * CS_S4_IN_LOGIN.  Start login timer.
1119 		 */
1120 		ic->ic_state_timeout = timeout(idm_login_timeout, ic,
1121 		    drv_usectohz(IDM_LOGIN_SECONDS*1000000));
1122 		break;
1123 	case CS_S4_IN_LOGIN:
1124 		if (ic->ic_conn_type == CONN_TYPE_INI) {
1125 			mutex_enter(&ic->ic_state_mutex);
1126 			ic->ic_state_flags |= CF_LOGIN_READY;
1127 			cv_signal(&ic->ic_state_cv);
1128 			mutex_exit(&ic->ic_state_mutex);
1129 		}
1130 		break;
1131 	case CS_S5_LOGGED_IN:
1132 		ASSERT(!ic->ic_ffp);
1133 		/*
1134 		 * IDM can go to FFP before the initiator but it
1135 		 * needs to go to FFP after the target (IDM target should
1136 		 * go to FFP after notify_ack).
1137 		 */
1138 		idm_status = idm_ffp_enable(ic);
1139 		if (idm_status != IDM_STATUS_SUCCESS) {
1140 			idm_conn_event(ic, CE_TRANSPORT_FAIL, NULL);
1141 		}
1142 
1143 		if (ic->ic_reinstate_conn) {
1144 			/* Connection reinstatement is complete */
1145 			idm_conn_event_locked(ic->ic_reinstate_conn,
1146 			    CE_CONN_REINSTATE_SUCCESS, NULL, CT_NONE);
1147 		}
1148 		break;
1149 	case CS_S6_IN_LOGOUT:
1150 		break;
1151 	case CS_S7_LOGOUT_REQ:
1152 		/* Start logout timer for target connections */
1153 		if (IDM_CONN_ISTGT(ic)) {
1154 			ic->ic_state_timeout = timeout(idm_logout_req_timeout,
1155 			    ic, drv_usectohz(IDM_LOGOUT_SECONDS*1000000));
1156 		}
1157 		break;
1158 	case CS_S8_CLEANUP:
1159 		/* Close connection (if it's not already closed) */
1160 		if (IDM_CONN_ISTGT(ic)) {
1161 			ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
1162 		} else {
1163 			ic->ic_transport_ops->it_ini_conn_disconnect(ic);
1164 		}
1165 
1166 		/* Stop executing active tasks */
1167 		idm_task_abort(ic, NULL, AT_INTERNAL_SUSPEND);
1168 
1169 		/* Start logout timer */
1170 		ic->ic_state_timeout = timeout(idm_cleanup_timeout, ic,
1171 		    drv_usectohz(IDM_CLEANUP_SECONDS*1000000));
1172 		break;
1173 	case CS_S10_IN_CLEANUP:
1174 		break;
1175 	case CS_S9A_REJECTED:
1176 		/*
1177 		 * We never finished establishing the connection so no
1178 		 * disconnect.  No client notificatiosn because the client
1179 		 * rejected the connection.
1180 		 */
1181 		idm_refcnt_async_wait_ref(&ic->ic_refcnt,
1182 		    &idm_conn_reject_unref);
1183 		break;
1184 	case CS_S9_INIT_ERROR:
1185 		if (IDM_CONN_ISTGT(ic)) {
1186 			ic->ic_transport_ops->it_tgt_conn_disconnect(ic);
1187 		} else {
1188 			mutex_enter(&ic->ic_state_mutex);
1189 			ic->ic_state_flags |= CF_ERROR;
1190 			ic->ic_conn_sm_status = IDM_STATUS_FAIL;
1191 			cv_signal(&ic->ic_state_cv);
1192 			mutex_exit(&ic->ic_state_mutex);
1193 			if (ic->ic_last_state != CS_S1_FREE &&
1194 			    ic->ic_last_state != CS_S2_XPT_WAIT) {
1195 				ic->ic_transport_ops->it_ini_conn_disconnect(
1196 				    ic);
1197 			} else {
1198 				(void) idm_notify_client(ic, CN_CONNECT_FAIL,
1199 				    NULL);
1200 			}
1201 		}
1202 		/*FALLTHROUGH*/
1203 	case CS_S11_COMPLETE:
1204 		/*
1205 		 * No more traffic on this connection.  If this is an
1206 		 * initiator connection and we weren't connected yet
1207 		 * then don't send the "connect lost" event.
1208 		 * It's useful to the initiator to know whether we were
1209 		 * logging in at the time so send that information in the
1210 		 * data field.
1211 		 */
1212 		if (IDM_CONN_ISTGT(ic) ||
1213 		    ((ic->ic_last_state != CS_S1_FREE) &&
1214 		    (ic->ic_last_state != CS_S2_XPT_WAIT))) {
1215 			(void) idm_notify_client(ic, CN_CONNECT_LOST,
1216 			    (uintptr_t)(ic->ic_last_state == CS_S4_IN_LOGIN));
1217 		}
1218 
1219 		/* Abort all tasks */
1220 		idm_task_abort(ic, NULL, AT_INTERNAL_ABORT);
1221 
1222 		/*
1223 		 * Handle terminal state actions on the global taskq so
1224 		 * we can clean up all the connection resources from
1225 		 * a separate thread context.
1226 		 */
1227 		idm_refcnt_async_wait_ref(&ic->ic_refcnt, &idm_conn_unref);
1228 		break;
1229 	case CS_S12_ENABLE_DM:
1230 
1231 		/*
1232 		 * The Enable DM state indicates the initiator to initiate
1233 		 * the hello sequence and the target to get ready to accept
1234 		 * the iSER Hello Message.
1235 		 */
1236 		idm_status = (IDM_CONN_ISINI(ic)) ?
1237 		    ic->ic_transport_ops->it_ini_enable_datamover(ic) :
1238 		    ic->ic_transport_ops->it_tgt_enable_datamover(ic);
1239 
1240 		if (idm_status == IDM_STATUS_SUCCESS) {
1241 			idm_conn_event(ic, CE_ENABLE_DM_SUCCESS, NULL);
1242 		} else {
1243 			idm_conn_event(ic, CE_ENABLE_DM_FAIL, NULL);
1244 		}
1245 
1246 		break;
1247 	}
1248 }
1249 
1250 
1251 static void
1252 idm_conn_unref(void *ic_void)
1253 {
1254 	idm_conn_t *ic = ic_void;
1255 
1256 	/*
1257 	 * Client should not be notified that the connection is destroyed
1258 	 * until all references on the idm connection have been removed.
1259 	 * Otherwise references on the associated client context would need
1260 	 * to be tracked separately which seems like a waste (at least when
1261 	 * there is a one for one correspondence with references on the
1262 	 * IDM connection).
1263 	 */
1264 	if (IDM_CONN_ISTGT(ic)) {
1265 		(void) idm_notify_client(ic, CN_CONNECT_DESTROY, NULL);
1266 		idm_svc_conn_destroy(ic);
1267 	} else {
1268 		/* Initiator may destroy connection during this call */
1269 		(void) idm_notify_client(ic, CN_CONNECT_DESTROY, NULL);
1270 	}
1271 }
1272 
1273 static void
1274 idm_conn_reject_unref(void *ic_void)
1275 {
1276 	idm_conn_t *ic = ic_void;
1277 
1278 	ASSERT(IDM_CONN_ISTGT(ic));
1279 
1280 	/* Don't notify the client since it rejected the connection */
1281 	idm_svc_conn_destroy(ic);
1282 }
1283 
1284 
1285 
1286 static idm_pdu_event_action_t
1287 idm_conn_sm_validate_pdu(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx,
1288 	idm_pdu_t *pdu)
1289 {
1290 	char			*reason_string;
1291 	idm_pdu_event_action_t	action;
1292 
1293 	ASSERT((event_ctx->iec_pdu_event_type == CT_RX_PDU) ||
1294 	    (event_ctx->iec_pdu_event_type == CT_TX_PDU));
1295 
1296 	/*
1297 	 * Let's check the simple stuff first.  Make sure if this is a
1298 	 * target connection that the PDU is appropriate for a target
1299 	 * and if this is an initiator connection that the PDU is
1300 	 * appropriate for an initiator.  This code is not in the data
1301 	 * path so organization is more important than performance.
1302 	 */
1303 	switch (IDM_PDU_OPCODE(pdu)) {
1304 	case ISCSI_OP_NOOP_OUT:
1305 	case ISCSI_OP_SCSI_CMD:
1306 	case ISCSI_OP_SCSI_TASK_MGT_MSG:
1307 	case ISCSI_OP_LOGIN_CMD:
1308 	case ISCSI_OP_TEXT_CMD:
1309 	case ISCSI_OP_SCSI_DATA:
1310 	case ISCSI_OP_LOGOUT_CMD:
1311 	case ISCSI_OP_SNACK_CMD:
1312 		/*
1313 		 * Only the initiator should send these PDU's and
1314 		 * only the target should receive them.
1315 		 */
1316 		if (IDM_CONN_ISINI(ic) &&
1317 		    (event_ctx->iec_pdu_event_type == CT_RX_PDU)) {
1318 			reason_string = "Invalid RX PDU for initiator";
1319 			action = CA_RX_PROTOCOL_ERROR;
1320 			goto validate_pdu_done;
1321 		}
1322 
1323 		if (IDM_CONN_ISTGT(ic) &&
1324 		    (event_ctx->iec_pdu_event_type == CT_TX_PDU)) {
1325 			reason_string = "Invalid TX PDU for target";
1326 			action = CA_TX_PROTOCOL_ERROR;
1327 			goto validate_pdu_done;
1328 		}
1329 		break;
1330 	case ISCSI_OP_NOOP_IN:
1331 	case ISCSI_OP_SCSI_RSP:
1332 	case ISCSI_OP_SCSI_TASK_MGT_RSP:
1333 	case ISCSI_OP_LOGIN_RSP:
1334 	case ISCSI_OP_TEXT_RSP:
1335 	case ISCSI_OP_SCSI_DATA_RSP:
1336 	case ISCSI_OP_LOGOUT_RSP:
1337 	case ISCSI_OP_RTT_RSP:
1338 	case ISCSI_OP_ASYNC_EVENT:
1339 	case ISCSI_OP_REJECT_MSG:
1340 		/*
1341 		 * Only the target should send these PDU's and
1342 		 * only the initiator should receive them.
1343 		 */
1344 		if (IDM_CONN_ISTGT(ic) &&
1345 		    (event_ctx->iec_pdu_event_type == CT_RX_PDU)) {
1346 			reason_string = "Invalid RX PDU for target";
1347 			action = CA_RX_PROTOCOL_ERROR;
1348 			goto validate_pdu_done;
1349 		}
1350 
1351 		if (IDM_CONN_ISINI(ic) &&
1352 		    (event_ctx->iec_pdu_event_type == CT_TX_PDU)) {
1353 			reason_string = "Invalid TX PDU for initiator";
1354 			action = CA_TX_PROTOCOL_ERROR;
1355 			goto validate_pdu_done;
1356 		}
1357 		break;
1358 	default:
1359 		reason_string = "Unknown PDU Type";
1360 		action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
1361 		    CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
1362 		goto validate_pdu_done;
1363 	}
1364 
1365 	/*
1366 	 * Now validate the opcodes against the current state.
1367 	 */
1368 	reason_string = "PDU not allowed in current state";
1369 	switch (IDM_PDU_OPCODE(pdu)) {
1370 	case ISCSI_OP_NOOP_OUT:
1371 	case ISCSI_OP_NOOP_IN:
1372 		/*
1373 		 * Obviously S1-S3 are not allowed since login hasn't started.
1374 		 * S8 is probably out as well since the connection has been
1375 		 * dropped.
1376 		 */
1377 		switch (ic->ic_state) {
1378 		case CS_S4_IN_LOGIN:
1379 		case CS_S5_LOGGED_IN:
1380 		case CS_S6_IN_LOGOUT:
1381 		case CS_S7_LOGOUT_REQ:
1382 			action = CA_FORWARD;
1383 			goto validate_pdu_done;
1384 		case CS_S8_CLEANUP:
1385 		case CS_S10_IN_CLEANUP:
1386 			action = CA_DROP;
1387 			break;
1388 		default:
1389 			action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
1390 			    CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
1391 			goto validate_pdu_done;
1392 		}
1393 		/*NOTREACHED*/
1394 	case ISCSI_OP_SCSI_CMD:
1395 	case ISCSI_OP_SCSI_RSP:
1396 	case ISCSI_OP_SCSI_TASK_MGT_MSG:
1397 	case ISCSI_OP_SCSI_TASK_MGT_RSP:
1398 	case ISCSI_OP_SCSI_DATA:
1399 	case ISCSI_OP_SCSI_DATA_RSP:
1400 	case ISCSI_OP_RTT_RSP:
1401 	case ISCSI_OP_SNACK_CMD:
1402 	case ISCSI_OP_TEXT_CMD:
1403 	case ISCSI_OP_TEXT_RSP:
1404 		switch (ic->ic_state) {
1405 		case CS_S5_LOGGED_IN:
1406 		case CS_S6_IN_LOGOUT:
1407 		case CS_S7_LOGOUT_REQ:
1408 			action = CA_FORWARD;
1409 			goto validate_pdu_done;
1410 		case CS_S8_CLEANUP:
1411 		case CS_S10_IN_CLEANUP:
1412 			action = CA_DROP;
1413 			break;
1414 		default:
1415 			action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
1416 			    CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
1417 			goto validate_pdu_done;
1418 		}
1419 		/*NOTREACHED*/
1420 	case ISCSI_OP_LOGOUT_CMD:
1421 	case ISCSI_OP_LOGOUT_RSP:
1422 	case ISCSI_OP_REJECT_MSG:
1423 	case ISCSI_OP_ASYNC_EVENT:
1424 		switch (ic->ic_state) {
1425 		case CS_S5_LOGGED_IN:
1426 		case CS_S6_IN_LOGOUT:
1427 		case CS_S7_LOGOUT_REQ:
1428 			action = CA_FORWARD;
1429 			goto validate_pdu_done;
1430 		case CS_S8_CLEANUP:
1431 		case CS_S10_IN_CLEANUP:
1432 			action = CA_DROP;
1433 			break;
1434 		default:
1435 			action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
1436 			    CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
1437 			goto validate_pdu_done;
1438 		}
1439 		/*NOTREACHED*/
1440 	case ISCSI_OP_LOGIN_CMD:
1441 	case ISCSI_OP_LOGIN_RSP:
1442 		switch (ic->ic_state) {
1443 		case CS_S3_XPT_UP:
1444 		case CS_S4_IN_LOGIN:
1445 			action = CA_FORWARD;
1446 			goto validate_pdu_done;
1447 		default:
1448 			action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
1449 			    CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
1450 			goto validate_pdu_done;
1451 		}
1452 		/*NOTREACHED*/
1453 	default:
1454 		/* This should never happen -- we already checked above */
1455 		ASSERT(0);
1456 		/*NOTREACHED*/
1457 	}
1458 
1459 	action = ((event_ctx->iec_pdu_event_type == CT_TX_PDU) ?
1460 	    CA_TX_PROTOCOL_ERROR : CA_RX_PROTOCOL_ERROR);
1461 
1462 validate_pdu_done:
1463 	if (action != CA_FORWARD) {
1464 		DTRACE_PROBE2(idm__int__protocol__error,
1465 		    idm_conn_event_ctx_t *, event_ctx,
1466 		    char *, reason_string);
1467 	}
1468 
1469 	return (action);
1470 }
1471 
1472 /* ARGSUSED */
1473 void
1474 idm_pdu_tx_protocol_error(idm_conn_t *ic, idm_pdu_t *pdu)
1475 {
1476 	/*
1477 	 * Return the PDU to the caller indicating it was a protocol error.
1478 	 * Caller can take appropriate action.
1479 	 */
1480 	idm_pdu_complete(pdu, IDM_STATUS_PROTOCOL_ERROR);
1481 }
1482 
1483 void
1484 idm_pdu_rx_protocol_error(idm_conn_t *ic, idm_pdu_t *pdu)
1485 {
1486 	/*
1487 	 * Forward PDU to caller indicating it is a protocol error.
1488 	 * Caller should take appropriate action.
1489 	 */
1490 	(*ic->ic_conn_ops.icb_rx_error)(ic, pdu, IDM_STATUS_PROTOCOL_ERROR);
1491 }
1492 
1493 idm_status_t
1494 idm_notify_client(idm_conn_t *ic, idm_client_notify_t cn, uintptr_t data)
1495 {
1496 	/*
1497 	 * We may want to make this more complicated at some point but
1498 	 * for now lets just call the client's notify function and return
1499 	 * the status.
1500 	 */
1501 	cn = (cn > CN_MAX) ? CN_MAX : cn;
1502 	IDM_SM_LOG(CE_NOTE, "idm_notify_client: ic=%p %s(%d)\n",
1503 	    (void *)ic, idm_cn_strings[cn], cn);
1504 	return ((*ic->ic_conn_ops.icb_client_notify)(ic, cn, data));
1505 }
1506 
1507 static idm_status_t
1508 idm_ffp_enable(idm_conn_t *ic)
1509 {
1510 	idm_status_t rc;
1511 
1512 	/*
1513 	 * On the initiator side the client will see this notification
1514 	 * before the actual login succes PDU.  This shouldn't be a big
1515 	 * deal since the initiator drives the connection.  It can simply
1516 	 * wait for the login response then start sending SCSI commands.
1517 	 * Kind ugly though compared with the way things work on target
1518 	 * connections.
1519 	 */
1520 	mutex_enter(&ic->ic_state_mutex);
1521 	ic->ic_ffp = B_TRUE;
1522 	mutex_exit(&ic->ic_state_mutex);
1523 
1524 	rc = idm_notify_client(ic, CN_FFP_ENABLED, NULL);
1525 	if (rc != IDM_STATUS_SUCCESS) {
1526 		mutex_enter(&ic->ic_state_mutex);
1527 		ic->ic_ffp = B_FALSE;
1528 		mutex_exit(&ic->ic_state_mutex);
1529 	}
1530 	return (rc);
1531 }
1532 
1533 static void
1534 idm_ffp_disable(idm_conn_t *ic, idm_ffp_disable_t disable_type)
1535 {
1536 	mutex_enter(&ic->ic_state_mutex);
1537 	ic->ic_ffp = B_FALSE;
1538 	mutex_exit(&ic->ic_state_mutex);
1539 
1540 	/* Client can't "fail" CN_FFP_DISABLED */
1541 	(void) idm_notify_client(ic, CN_FFP_DISABLED,
1542 	    (uintptr_t)disable_type);
1543 }
1544 
1545 static void
1546 idm_initial_login_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
1547 {
1548 	ASSERT((event_ctx->iec_event == CE_LOGIN_RCV) ||
1549 	    (event_ctx->iec_event == CE_LOGIN_SND));
1550 
1551 	/*
1552 	 * Currently it's not clear what we would do here -- since
1553 	 * we went to the trouble of coding an "initial login" hook
1554 	 * we'll leave it in for now.  Remove before integration if
1555 	 * it's not used for anything.
1556 	 */
1557 	ic->ic_state_flags |= CF_INITIAL_LOGIN;
1558 }
1559 
1560 static void
1561 idm_login_success_actions(idm_conn_t *ic, idm_conn_event_ctx_t *event_ctx)
1562 {
1563 	idm_pdu_t		*pdu = (idm_pdu_t *)event_ctx->iec_info;
1564 	iscsi_login_hdr_t	*login_req =
1565 	    (iscsi_login_hdr_t *)pdu->isp_hdr;
1566 
1567 	ASSERT((event_ctx->iec_event == CE_LOGIN_SUCCESS_RCV) ||
1568 	    (event_ctx->iec_event == CE_LOGIN_SUCCESS_SND));
1569 
1570 	/*
1571 	 * Save off CID
1572 	 */
1573 	mutex_enter(&ic->ic_state_mutex);
1574 	ic->ic_login_cid = ntohs(login_req->cid);
1575 	ic->ic_login_info_valid =  B_TRUE;
1576 
1577 	mutex_exit(&ic->ic_state_mutex);
1578 }
1579